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Science china chemistry 2010年第3期53卷 561-567页

作者： WANG YuFeng,SONG ZhanBo,CHEN ChunXia & PENG JinSong department of chemistry and chemical {3.,College of Science,Northeast Forestry University,Harbin 150040,china department of chemistry and chemical {3. College of Science Northeast Forestry University Harbin China

Catalytic performance of different cation-exchanged montmorillonite clays has been investigated in the Pictet-Spengler C-C bond forming reaction.H+-Montmorillonite was found to be a very efficient and reusable catalyst for the endo cyclization of β-phenylethylamine derivatives with aldehydes under solvent-free *** addition,an aqueous condensation version for the synthesis of tetrahydro-β-carbolines using the H+-montmorillonite catalyst has been *** these environmentally friendly processes,the use of organic solvents was avoided and the catalyst was recycled with maintenance of high catalytic activity.

关键词： heterogeneous catalysis catalyst recycling mesoporous materials green synthesis

Synthesis of Macrocyclic Arsinous Acid Esters

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Chinese chemical Letters 1999年第12期10卷 0-0页

作者： Xin You CHENI Ying Qin YANG Wen Tian TAO(1’department of chemistry, Xiaogan teachers College, Hubei 43.100)(2department of chemistry, Xinyang teachers College, Henan 464000)(3.0} of chemistry, Wuhan University, Wuhan 43.072) department of chemistry Xiaogan Teachers College Hubei 432100 China department of chemistry Xinyang Teachers College Henan 464000 China department of chemistry Wuhan University Wuhan 430072 China

The reactions of the his (dimethylamino) alkylarsine with dids lead to the formations ofmacrocyclic arsinous acid esters. The synthesis of title compounds was described and theirslructures were characterized by elemen... 详细信息

关键词： Bis (dimethylamino) alkylarsine macrocyclic arsinous acid ester synthesis.

SYNTHESIS AND CHARACTERIZATION OF PHTHALAZINONE POLY(ARYL ETHER SULFONE KETONE)WITH CARBONYL GROUP

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Chinese Journal of Polymer Science 2002年第3期20卷 225-229页

作者： Ying-nan Xuan Yan Gao Yong Huang Xi-gao Jian Laboratory of Cellulose and Lignocellulosics chemistry Guangzhou Institute of chemistry Chinese Academy of Sciences, Guangzhou 510650{3. Institute of chemistry Chinese Academy of Sciences, Beijing 100080{3. department of Polymer Science, College of chemical engineering Dalian University of Technology, Dalian 116012,{3. 中科院广州化学所 Laboratory of Cellulose and Lignocellulosics Chemistry CAS Guangzhou 510650 department of Polymer Science College of Chemical Engineering Dalian University of Technology Dalian 116012

A kind of novel heat-resistant, high performance engineering thermoplastic phthalazinone poly(aryl ether sulfone ketone) (PPESK) containing a carboxyl group in its side chain was prepared by the nucleophilic displacement reaction of 4-(4-hydroxylphenyl)- 1 (2H)-phthalazinone with di(4-chlorophenyl) sulfone, 4,4'-difluoro-benzophenone and phenolphthalin in sulfolane in the presence of K2CO3.to produce high molecular weight polymers which can be dissolved in some polar solvents such as chloroform and nitrobenzene at room temperature and can be easily cast into flexible, yellowish and transparent films. PPESK is an amorphous polymer having a decomposition temperature above 400degreesC, which indicates that it has high thermal stability. At the same time, the thermal properties of PPESKs with dicyandiamide (DICY) as curing agent indicated that the heat-resistance properties of the PPESKs are improved after curing. The apparent activation energy (A-E) of the cross-linking reaction and the reaction order (n) of PPESK/DICY were found to be 52.2 kJ/mol and ca. 1.0, respectively. Therefore, the cross-linking reaction is approximately a first order reaction.

关键词： poly(aryl ether sulfone ketone) synthesis active pendant group

A　NEW　EMPIRICAL　EQUATION　ON　CORRELATION　BETWEEN　TOPOLOGIC　INDEX　AND　PHYSICO－chemical　PROPERTIES　OF　NORMAL　PARAFFINS

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Chinese chemical Letters 1996年第8期7卷 771-772页

作者： Cai Hua NI Xian Yu ZENG ping MEI(department of chemistry, JingZhou teachers’ College department of Polymer Science, Beijing Universityof chemical Techology department of Applied chemistry, Jianghan Petroleum Institute). department of chemistry Jingzhou Teachers' College department of Polymer Science Beijing Univ. of Chemical Technology department of Applied chemistry Jianghan Petroleum Institute

An empirical epuation to reveal relations between topological index(ZG)and physico chemical portes of normal paraffins is proposed as follows; p= a ig ZG/Nx + b, where P standsfor a physico-chemical property, N is the number of carbon atoms in the molecule, and ZG is thetopological index proposed by Hosoya a, b, and x are constants related to a certain Phyaicochemical property. Thirteen properties are calculated ac this equation The values of theseproperties caiculated are Close to those from experiments.

关键词：

Carbendazim residue in plant-based foods in china:Consecutive surveys from 2011 to 2020

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Environmental Science and Ecotechnology 2024年第1期17卷 109-118页

作者： Dou Wang Guiling Yang Xiao Yun Ting Luo Hao Guo Liying Pan wei Du Yanhua Wang Qiang Wang Pu Wang Qinghua Zhang Yun Li nan Lin State Key Laboratory for Managing Biotic and chemical Threats to the Quality and Safety of Agro-products Laboratory(Hangzhou)for Risk Assessment of Agricultural Products of Ministry of AgricultureInstitute of Agro-product Safety and NutritionZhejiang Academy of Agricultural SciencesHangzhou310021ZhejiangChina College of Urban and Environmental Sciences Peking UniversityBeijing100871China Yunnan Provincial Key Laboratory of Soil Carbon Sequestration and Pollution Control Faculty of Environmental Science&EngineeringKunming University of Science&TechnologyKunming650500China Hubei Key Laboratory of Industrial Fume and Dust Pollution Control School of Environment and HealthJianghan UniversityWuhan430056China State Key Laboratory of Environmental chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China Key Laboratory of Agro-Product Quality and Safety of Ministry of Agriculture Institute of Quality Standards and Testing Technology for Agro-ProductsChinese Academy of Agricultural SciencesBeijing100081China department of Environmental Health School of Public HealthShanghai Jiao Tong UniversityShanghai200025China

Carbendazim,a widely used fungicide in china,has been found to have reproductive toxicity and mutagenic ***,information on the spatial-temporal variations of carbendazim residues in food in china is ***,we investigated the presence of carbendazim in china's plant-based foods from 2011 to 2020,evaluated the spatial-temporal characteristics,and assessed the associated exposure risks in the Chinese *** results revealed a high detection frequency of carbendazim in fruits(26.4%)and high concentrations in vegetables(~110 mg kg^(-1)),indicating widespread misuse of the *** acute risks of consuming certain vegetables and cereals exceeded the recommended limits by up to 12 and 5 times,*** there has been a decline in carbendazim residue levels in food since the implementation of the Chinese government's action plan for zero growth of pesticide use in 2015,some provinces still exhibited high levels of carbendazim in multiple food categories,which were positively correlated with annual pesticide *** highlight that carbendazim contamination reflects the broader issue of pesticide use in *** emphasizes the need for committed and targeted national policies to reduce carbendazim residues in food and suggests that such measures could also regulate the use of other pesticides,given that pesticide abuse in china is not limited to specific *** call for the re-evaluation of maximum residue limits of carbendazim,particularly in highly consumed foods such as cereals.

关键词： Carbendazim Plant-based foods china Spatial-temporal variations Exposure and risk assessment

A new approach to the synthesis of diacetals(diketals) pentaerythritol catalyzed by SO_3.-functionalized ionic liquids

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Chinese chemical Letters 2010年第5期21卷 524-528页

作者： Yuan Yuan Wang,Yan nan Xu,Zhi Zhong Wang,Li Yi Dai Shanghai Key Laboratory of Green chemistry and chemical Process,{3. of chemistry, East china Normal University,Shanghai 200062,china Shanghai Key Laboratory of Green chemistry and chemical Process Department of Chemistry East China Normal University Shanghai 200062 China

In this article,an efficient,simple and environmentally friendly approach to the synthesis of diacetals(diketals) pentaerythritol using SOH-functionalized ionic liquids(ILs) as catalysts was *** ILs show high catalytic activity and reusability with good to excellent yields of the desired *** method has been used to determine the acidity order of these ionic liquids and the results are consistent with the catalytic activities observed in acetalization *** product yield of 93.was observed on using[PSPy][OTf]as catalyst and it can be reused at least 8 times without obvious activity loss.

关键词： SO3.-functionalized ionic liquids Diacetals(diketals) pentaerythritol Catalyze Hammett method Reusability

Moisture‑Electric–Moisture‑Sensitive Heterostructure Triggered Proton Hopping for Quality‑Enhancing Moist‑Electric Generator

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nano-Micro Letters 2024年第3期16卷 351-366页

作者： Ya’nan Yang Jiaqi Wang Zhe Wang Changxiang Shao Yuyang Han Ying Wang Xiaoting Liu Xiaotong Sun Liru Wang Yuanyuan Li Qiang Guo Wenpeng Wu nan Chen Liangti Qu Key Laboratory of Cluster Science Ministry of Education of ChinaKey Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081People’s Republic of China Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing 314019People’s Republic of China department of chemistry Key Laboratory of Organic Optoelectronics&Molecular EngineeringMinistry of EducationTsinghua UniversityBeijing 100084People’s Republic of China

Moisture-enabled electricity(ME)is a method of converting the potential energy of water in the external environment into electrical energy through the interaction of functional materials with water molecules and can be directly applied to energy harvesting and signal ***,ME can be unreliable in numerous applications due to its sluggish response to moisture,thus sacrificing the value of fast energy harvesting and highly accurate information ***,by constructing a moisture-electric-moisture-sensitive(ME-MS)heterostructure,we develop an efficient ME generator with ultra-fast electric response to moisture achieved by triggering Grotthuss protons hopping in the sensitized ZnO,which modulates the heterostructure built-in interfacial potential,enables quick response(0.43. s),an unprecedented ultra-fast response rate of 972.4 mV s^(−1),and a durable electrical signal output for 8 h without any *** research provides an efficient way to generate electricity and important insight for a deeper understanding of the mechanisms of moisture-generated carrier migration in ME generator,which has a more comprehensive working scene and can serve as a typical model for human health monitoring and smart medical electronics design.

关键词： Moist-electric generators Grotthuss proton hopping Fast response Durable electrical output Personal health monitoring

The Dramatic Effect of Metal Precursor on the Catalytic Performance of Co/Sio_2 Catalyst for CO_2 Reforming of CH_4

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Chinese chemical Letters 2000年第2期11卷 181-184页

作者： Chuan Jing HUANG1,2 Jin Hua FEI1 Dong Jie WANG1,3.Xiao Ming ZHENG1 (1Institute of Catalysis, Xixi campus, Zhejiang University, Hangzhou 3.10028 2department of chemistry, Huaibei Coal teachers College, Huaibei 23.000 3.0} of chemistry, Ningbo Uni Institute of Catalysis Xixi Campus Zhejiang University Hangzhou 310028 China department of chemistry Huaibei Coal Teachers College Huaibei 235000 China department of chemistry Ningbo University Ningbo 315000 China

The cobalt precursor affects the catalytic performance of Co/SiO_2 catalyst remarkably. The catalyst prepared from cobalt acetate exhibits excellent activity, stability and resistance to carbon deposition.

关键词： CO_2 reforming of CH_4 synthesis gas Co/SiO_2 catalyst precursor.

A New Model for Calculation of Standard Entropies of Solid Compounds Ⅳ-Calculation of Standard Entropies of Solid Complex Silicates S

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Chinese chemical Letters 1998年第5期9卷 477-479页

作者： Xun Min YU(department of chemistry, Jingzhou teachers College, Hubei 43.100) department of chemistry Jingzhou Teachers College Hubei 434100 China

This paper presents a new model for the calculation of the standard entropies of solidcomplex silicates as follows.4. =53.63.9914-72.81 J/kmol (R=0.9915, Sd=5.3.)Sixty complex silicates have been investigated, and go... 详细信息

关键词： standard entropy silicate pseudo-positiveion

Carbon coated LaFe_(0.92)Pd_(0.08)O_(3. composites for catalytic transfer hydrogenation:Balance in the ability of substrates adsorption and conversion

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nano Research 2024年第5期17卷 3724-3732页

作者： Bowen Wang nan Zhang Ping Xiao Jian Zhang Sónia A.C.Carabineiro Junjiang Zhu Hubei Key Laboratory of Biomass Fibers and Eco-dyeing&Finishing College of Chemistry and Chemical EngineeringWuhan Textile UniversityWuhan 430200China College of chemistry and Materials engineering Wenzhou UniversityWenzhou 325035China LAQV-REQUIMTE Department of ChemistryNOVA School of Science and TechnologyUniversidade NOVA de LisboaLargo da Torre2829-516 CaparicaPortugal

Catalytic transfer hydrogenation(CTH)is a green and efficient pathway for selective hydrogenation of unsaturated aldehydes and ***,managing the abilities of solid catalysts to adsorb substrates and to convert them into desired products is a challenging ***,we report the synthesis of carbon coated LaFe_(0.92)Pd_(0.08)O_(3. composites(LFPO-8@C)for CTH of benzaldehyde(BzH)into benzyl alcohol(BzOH),using isopropanol(IPA)as hydrogen *** coating with carbon improves the ability to adsorb/transfer reactants from solution to active sites,and the doping of Pd2+at Fe3.site strengthens the ability of LaFeO_(3. to convert BzH into BzOH.A balanced point between them(i.e.,abilities to adsorb BzH and to convert BzH into BzOH)is obtained at LFPO-8@C,which exhibits a BzOH formation rate of 3.88 mmol·gcat^(-1)·h^(-1) at 180℃ for 3.h,which is 1.50 and 2.72 times faster than those of LFPO-8 and LaFeO_(3.@C.A reaction mechanism is proposed,in which the acidic sites(e.g.,Fe^(4+),oxygen vacancy)are used for the activation of C=O bond of BzH and O-H bond of IPA,and the basic sites(e.g.,lattice oxygen)for the activation ofα-H(O-H)bond of IPA.

关键词： LaFe_(0.92)Pd_(0.08)O_(3. porous carbon catalytic transfer hydrogenation isopropanol reaction mechanism